Concentrating evaporator



1 G. ENGEL, SR

CONCENTRATING EVAPORATQR Filed April "17. 1920 r Patented AugQZS, 1923.

GODFREY EN'GEL, SR., OF BROOKLYN, NEN YORK ASSIGNOPJ T BUFFALO FOUNDRY & MACHINE (30., 0F BUFFALO, NEW YOBK,'A EORPORATION OF NEW YORK.

CONCENTRATING EVAPORATOR.

Application filed April 17,

pans and evaporators of the calandria type.

The objects of the invention are to obtain a maximum of heating surface with a minimum cubic content at the level of the calandria; to promote the circulation and the crystallization; to reduce the time necessary for the complete cycle of operation; to enable the operation at lower temperatures than has been possible heretofore; to increase the capacity and the yield of crystal lization; to simplify the structure and to favor the complete discharge of sugar from all surfaces and to provide'efl'ective circulation of the steam or heating fluid.

These objects I have accomplished by a novel construction, combination and arrangement of parts, as will be more fully disclosed in the course of the following specification, reference being had. to the accompanying drawing, wherein I have illustrated the invention embodied in practical, commercial forms.

Inthe drawing: Figure 1 is a vertical part sectional view of a vacuum pan, constructed in accordance with and embodying my invention.

Figure 2 is an enlarged sectional view of the calandria structure, of Figure 1.

Figure 3 is a sectional elevation of a portion of a vacuum pan of modified construe tion. I

Figure 1 is a similar view of another modified form of construction.

The pan shown embodies a shell or casing 5 which differs from the usual structures of this type, in that it is contracted at a point 6 somewhat above the inclined bottom thereof, to provide a heating compartment in the lower section of the 1920. Serial m5. 374,659.

duced cubic capacity.

This throat, or constricted portion of the casing, is shown as produced by inserting a wall section 7 above the bottom of'the'panjl which is contracted toward its upper end to meet a correspondingly contracted portion 8 at the lower end of the adjoining section of the casing.

The calandria is made up of upper and other, so as to substantially fill up the enlarged space of increased capacity below the contracted portion of the pan.

The outer edges of the tube sheets are shown as connected together by the wall section 7 and the inner peripheral portions of the tube sheets are shown as connected together by a clown-take tube or plate 14-, stepped as indicated at 15 and 16 to take the ends of the shorter length tubes 12 and 13. i

The tubes are inclined, as indicated, downwardly and outwardly and the outermost tubes 11 are preferably arranged quite close to the outer edges of the tube sheets, so as to provide the maximum of heating surface.

The steam is admitted to the calandria through a suitable inlet or inlets 17, pro-'- vided in the outer wall of the calandria and condensation may betaken off through a drainage pipe or pipes 18. The incondensable gases may be taken off through upper and lower outlets 19 and'20, the upper serving for the escapeof the lighter gases and the lower for the heavier gases. This lower outlet may be extended by means of a. pipe indicated at 21 to the innermost and lower portion of the calandria.

The-outer wall section 7 of-the calandria 'may be slightly enlarged or bulged outpan of materially rewardly between the larger and smaller ends thereof substantially as indicated at 22, to provide a steam chest for facilitating circu lation of the steam to all of the heating tubes.

This invention, it will be seen, provides a maximum of heating surface with a minimum cubic content at the level where the calandria is covered by the syrup, facilitating rapid crystallization and accurate control of the operation.

The increase in diameter of the pan above the level of the contracted portion provides 'for any desired capacity of the pan, so that without aiiecting the ultimate capacity, a much more eflicient operation is attained than has been possible heretofore. As the granulation progresses, more liquor may be admitted up to the desired high level of the apparatus and by reason of the practically uninterrupted inclined surface of the upper tube sheet, the magma. may be quickly discharged. Thesteps 15 and 16 provided for the short length tubes may be inclined substantially parallel withthe upper tube sheet, as indicated, so as to prevent the magma from lodging thereon. By arranging the parts as shown, with the tube sheet of larger diameter at the bottom, the greatest heating surface is provided at the lower portion of the calandria and this facilitates and increases the circulation.

In the construction shown in Figure 3, the inner peripheries of the tube sheet-s 9 and 10 are connected by a. stepped shell 30. The upper tube sheet, as in the previous case, is connected! with the casing 5 In this case, however, the lower tube sheet 10 is not connected with the casing, but only with the shell 30. A flange 31 extending from the step of the shell 30 is also connected with the casing. The inlet 17 in this case, is connected with the casing between the flange 31 and the upper tube sheet 9*.

In the modification shown in Figure 4c, the calandria is of the floating type. In this case, the outer peripheries of the upper and lower tube sheets 9 and 10 are connected by a stepped shell 32 which, as in the modification shown in Figure 3, is concentric with the inner shell 14. The inlet 17 is connected with the inner shell 32 and in this modification the casing 5 may be cylindrical.

By means of this invention there is free dom of circulation and of discharge of the contents and. crystallization is cil'ected atlow temperatures and high vacuum. in the lower part of the apparatus and the process may be completed in one device, instead of being necessarily interdependent upon other vacuum pans.

That I claim is:

1. In apparatus of the character described,

sheets and other tubes between the inclined tube sheet and the stepped portion of the connecting shell. v

3. In apparatus of the character described,

an upper tube sheet, an inclined lower tube sheet, a shell connecting the edge portions of said tube sheets and having a stepped portion disposed in opposition to the. lower inclined tube sheet, tubes extending between the tube sheets and other tubes between the inclined lower tube sheet'and the stepped portion of the connecting shell.

4-. In apparatus of the character described, a calandria having oppositely disposed tube sheets with a wall connecting the same and provided with stepped portions opposed to and at different distances fromone'of the tube sheets and tubes of different lengths extending between said tube sheet and the stepped portions of said wall.

5. In apparatus of the character described, a calandria having oppositely disposed upper and lower tube sheets with a stepped wall. connecting the same, tubes engaged between the tube sheets and other tubes en-' gaged between one of the tube sheets and the stepped portions of the stepped wall.

6. In apparatus of the character described, a calandria comprising upper and lower tube sheets, one of greater diameter thanthe other, tubes extending between said sheets, a stepped wall connectingsaid tube sheets and tubes engaged between the stepped portion of said wall and one of the tube sheets;

7. In apparatus of the character described, a calandria comprising upper and lower tube sheets, one of greater diameter than the other, tubes extending bet-ween said sheets, a stepped down-take wall connecting said tube sheets and tubes engaged between the stepped portion of said down-take wall and one of the tube sheets.

the portion of the lower tube sheet which is of greater diameter than the upper tube sheet, a wall connecting the outer edges of said tube sheets of different diameter and forming the outer wall of the calandria and a portion of the outer wall of the apparatus and a wall connecting the inner edges of the tube sheets and forming a downtake.

9. The structure of claim 8 in which said outer wall of the calandria is substantially circular and is bulged outwardly to form a steam chamber entirely surrounding the tubes and in which a drainage chamber with an outlet is provided in the lowermost portion of the calandria.

10. The structure of claim 8 in which the outer wall of the apparatus is of less diameter at the upper tube sheet and is of greater diameter at I points above and below said upper tube sheet.

11. The structure of claim 10 in which the lower tube sheet is disposed within the portion of the wall of greater diameter.

In witness whereof, I have hereunto set my hand this 12th day of April, 1920.

GODFREY ENGEL, SR. 

